1. Make the filling by frying the onion in olive oil in a large saucepan until soft but not browned, then remove from heat and add the cooked spinach, chopped parsley and fennel seed.2. Preheat oven to 190C/Gas mark 5.3. Unroll the filo pastry and spread out in a pile with a damp cloth over.4. Take one sheet of filo pastry, place on a large board and brush all over with melted butter. Lay another sheet on top and brush that too. Cut into five equal-width strips.5. Place a teaspoon of filing 2.5 cm from the end of one strip. Fold the top corner over, making a triangular shape. Then fold the whole triangle over itself again and again until you get to the end of the strip. Brush with melted butter and place on greased baking sheet.6. Continue with the rest of the filo and filling in the same way until it is all used up and you have lots of little triangles on baking trays.7. Bake for 15 min until the pastry is golden-brown and crisp.